The invention relates to a fluid-actuable releaser for a friction clutch of a motor vehicle.
An annular cylindrical clutch releaser is known from EP-B-168 932 in which an annular piston is movably guided with its external diameter in a bore of a casing. With its internal diameter, the annular piston is guided on a sleeve which passes at one end into a radially outwardly projecting annular flange with which it is fastened in a sealed manner on the casing. The casing forms a pressure chamber together with one face end of the annular piston as well as the sleeve and the annular flange projecting from the sleeve. The piston carries a release bearing at the end remote from the pressure chamber. Although the known releaser can be produced with few constructional elements, it poses production problems as the sleeve guiding the annular piston radially internally has to be machined precisely close to its radially projecting annular flange and exact centering of the annular flange and adequate sealing of the annular flange relative to the casing have to be ensured.